The Friction Apparatus (FA) for the Surface Force Apparatus (SFA) is used for making fundamental measurements of interfacial friction and wear at a molecular level in the field of nanotribology. The FA services a growing interest in the fundamental study of interfacial friction at the nanoscale by research groups in universities and industry. The notable feature of the FA is that it is one of the few instruments that allow the contact profile of the surfaces that are being studied to be visualized while they are moving in contact under the influence of frictional forces. The FA also incorporates the facility for making quantitative measurements of the frictional force. The FA is a specialized instrument used for scientific research and requires skill and experience in laboratory techniques to operate it effectively.  The Friction Accessory will fit existing Surface Force Apparatuses (SFA), Mk2 or Mk4, with the possibility of being customised as a stand-alone device. How it works: The SFA technique uses two mica surfaces (lower and upper) mounted on curved silica discs. The surfaces are brought together under controlled conditions. The lower surface is mounted on a double cantilever spring and can be moved vertically into position with a micrometer. The upper surface is attached to the Friction Apparatus and can move horizontally by means of dual stainless steel springs across the lower surface. It is driven by a motor through a precision micrometer and translation stage at a constant speed ranging from 50 nm/s to 5000 nm/s. The Friction Apparatus is capable of measuring friction forces of up to a several Newtons. Normal loads of up to 1 Newton can be applied simultaneously. Strain gauges are glued to the springs. Any shear force that results from friction between the surfaces gives rise to a bending of the springs attached to the translation stage and thence to an electrical signal that is proportional to the friction force. The horizontal position of the translation stage as it moves across the lower surface is obtained from an electrical transducer. The data is recorded as frictional force against position of the translation stage. The original design was developed in our laboratories and is described by J.N. Israelachvili, in Science 240, 189 (1988) and J. Tribology 111, 675 (1989), and used in many subsequent publications. Our latest design is substantially improved. We have used the Friction Apparatus to measure frictional forces between curved mica surfaces. See the research paper below. However, there is no reason why the apparatus cannot be adapted for use with other surfaces of different geometry and sample holders/jigs modified to suit. Purchase: The Research School of Physical Sciences & Engineering at the Australian National University can supply a complete Friction Apparatus. To use the apparatus, the buyer needs a Surface Force Apparatusl, although a custom designed stand-alone device is possible. The assembly consists of numerous stainless steel components of intricate design, and includes a micrometer, wiring, limit switches, connectors, and a user manual. The precision mechanical assembly is carefully assembled and checked. It is the responsibility of the user to provide a variable speed motor to drive the micrometer and to obtain the electronic instrumentation needed to measure the voltage from the strain gauges. We use a lock-in amplifier but commercial strain gauge amplifiers can be used. We can advise on these matters.  2003 Price A$17,000 (Australian dollars).